Improvement in processes for casting hard metal on soft cast metal



2 Sheets-Sheet 2.

W. CQVBNTRY. Process for Gas-ting Hard Metal on Soft Cast Metal.

No. 215.210. Patented May 13, 1879.

NFETERS, FHOTOLITHOGRAPHER. WASHXNGTON. D C.

UNITED STATES PATENT OFFICE.

WILLIAM COVENTRY, OF NEWARK, NEW JERSEY.

IMPROVEMENT IN PROCESSES FOR CASTING HARD METAL 0N SOFT CAST METAL.

lSpecification forming part of Letters Patent No. 215,210, dated May 13, 1879; application filed November 22, 1878.

To all 'whom t may concern:

Be it known that I, WILLIAM GovEN'rRY, ot' Newark, in the county of Essex and State of New Jersey, have invented a new and useful Improvement in Processes for Casting Hard Metal upon Soft Gast Metal, which improvement is fully described in the following specitcation.

My invention relates t0 a new method of making jaws for stone-breakers and similar articles, and consists in forming a soft back upon a mass of hard iron by casting the same in two operations, in the following manner:

My method or process consists in first easting a plate of softiron or steel with apertures formed through it for uniting the same to the body of the die or jaw, as well as for ven tilating the mold, and then securing' the same in the top of amold, into which the harder metal is then poured, and with which the plate becomes firmly united in the operation of casting.

My invention is shown in the annexed drawings, in which Figure l isr an end view of a jaw, A, for a stone-breaker, the hard workingface being marked a and the soft back b. Fig. 2 is a view of the back of thejaw;l and Figs. 3 and 4 are detached views ot' a back plate, shown with round hole c c extending through it, to vent the casting and secure adhesion between the jaw and the plate. Figs. 5 and 6 are perspective views ot' the top and bottom of the mold with the soft plate secured in position, and Fig. 7 a transverse section ot' the mold across the middle of the inlet d.

Bis the top ot" the mold; C, the bottom, shown with a chill, D, placed in it to chill the working-face of the jaw. S S is the sand forming the mold. d representsinlets for the melted metal, which may be placed at any part of the mold, and d d are channels conducting the metal from the inlet into the mold beneath the plate secured in its top. .i v3 are ventilating-holes pierced in the top B, which may be dispensed with it' the sand is very porous. The holes o o in the plate are, however, indispensable, as no ventilation of the mold suflioes if the top be closed by a solid plate.

The body ot' the die may be formed of steel or hard iron, and may have a chilled face or not, as may be desired; but the soft back is essential to form a fitting surface if the body of the die be. too hard to plane easily.

While the casting of wrought-iron bars in the back of' a die produces cracks, and leads to the breaking of' the jaw when in use, I find that forming the .jaw or dic entirely ot' cast metal in two operations obviates this danger and produces a mass sound and solid throughout.

The size and shape ot' the holes in the soft plate are immaterial; but I generally make them smallest on the side next the jaw, that they may be dovetailed into the metal poured in contact with them.

Having thus shown the process, ot' making my improvement and the advantage of the jaws 'produced by suoli process, l claim the same as follows:

The process of casting stone-breaker jaws and similar articles, by first casting a plate of [soft .metal having apertures therein, placing the plate in the top ot' a mold, introducing a harder metal into the mold below the perforated plate, and causing the metal to rise to enter theapertures ot' the plate, as and for the purpose set forth.

In testimony that I claim the foregoing as myown I hereto subscribe my name in the presence ot' two witnesses.

WILLIAM GOVENTRY.

Witnesses:

Trios. S. CRANE, E. B. BURDETT, Jr. 

